Geminid MeteorMojave Desert, US

Many people have been lucky enough to see a "shooting star." However, this name is misleading because these brief streaks of light seen in the night sky actually have nothing to do with stars. Rather, these are tiny bits of debris usually left behind by a comet traveling through the Solar System. If the Earth passes through this debris trail, hundreds or even thousands of these cosmic bits enter the Earth's atmosphere. When these meteors enter the atmosphere, they are moving at speeds ranging from 11 km/sec (25,000 mph) to 72 km/sec (160,000 mph), and collide with numerous air molecules. These collisions create a vapor of atoms that is a mixture of energized atoms from the meteors and the atmosphere. As the electrons in these atoms fall back to their normal orbits, light is emitted, creating the bright trail light visible from the ground below.